Working with Data Pump enhancements in Oracle Database 12c: Part 1

Oracle® Data Pump (expdp, impdp) is a utility for exporting and importing
database objects in and across databases. While most database administrators
are aware of Data Pump, support for multitenant architecture in Oracle
Database 12c introduced changes to how Data Pump exports and imports data.

Introduction

This two-part blog series covers the changes to Oracle Data Pump
Export (expdp) technology and how to use it to take exports of components of
your database architecture.

The examples in this post focus on exports in the context of a
container database (CDB), which holds the Oracle metadata, and one or more
pluggable databases (PDBs), which hold your actual data.

Taking a full database export

A full database export doesn't necessarily include all of the data that you
might want. For example, you might think that when you connect to
the root container or CDB and take a full export of the database, the
export includes all of the PDBs that belong to it. However, that’s not the
case. The full export from the root container only exports the objects
that belong to the root container, and not the PDBs.

For example, consider a CDB named PRODCDB that's associated with four PDBs.
The following command pulls up detailed information about these databases:

The output shows that only the objects that belong to the root container are
exported with the full option. Unfortunately, there's no way to take an
export of all of the PDBs and the root container together.

Taking an export of a CDB

Taking an export of the CDB or root database isn't typically
required because it primarily hosts PDBs. However, if it becomes
necessary to perform this task, you can create a new CDB and plug the existing
PDBs. In these cases, administrators are usually most interested in taking an
export of the common users and roles.

For example, imagine that you have the following common user in a CDB:

Ideally, you wouldn't need to take an export of the root container
objects unless you had data that belongs to the common users in that
container.

Conclusion

Following the steps outlined in this blog post will help you use Data
Pump 12c's new features to export data more easily. Part
2 covers
Data Pump's restrictions on PDBs and how to export these databases.